The porcellanid crab Petrolisthes hastatus Stimpson, 1858, has been traditionally viewed as a highly variable species with a wide distribution in the West Pacific. For more than a century there has been taxonomic confusion of this species with morphologically similar taxa, some of which were synonymized with Stimpson’s taxon. We redefine P. hastatus, resurrect P. inermis as a valid species, discuss the status of P. tenkatei De Man, 1893, and describe a new species as P. elegantissimus from Indonesia.